package com.seu.me.netty.cases.httpfile;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpRequestDecoder;
import io.netty.handler.codec.http.HttpResponseEncoder;
import io.netty.handler.stream.ChunkedWriteHandler;

/**
 * @author liangfeihu
 * @since 2017/12/27 15:15.
 */
public class HttpFileServer {

    private static final String DEFAULT_URL = "/sources/";

    public void run(final int port, final String url) throws Exception {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup workerGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workerGroup)
                    .channel(NioServerSocketChannel.class)
                    .childHandler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            // 加入http的解码器
                            ch.pipeline().addLast("http-decoder", new HttpRequestDecoder());
                            // 加入ObjectAggregator解码器，作用是他会把多个消息转换为单一的FullHttpRequest或者FullHttpResponse
                            ch.pipeline().addLast("http-aggregator", new HttpObjectAggregator(65536));
                            // 加入http的编码器
                            ch.pipeline().addLast("http-encoder", new HttpResponseEncoder());
                            // 加入chunked 主要作用是支持异步发送的码流（大文件传输），但不专用过多的内存，防止java内存溢出
                            ch.pipeline().addLast("http-chunked", new ChunkedWriteHandler());
                            // 加入自定义处理文件服务器的业务逻辑handler
                            ch.pipeline().addLast("fileServerHandler", new HttpFileServerHandler(url));
                        }
                    });

            ChannelFuture future = b.bind(port).sync();
            System.out.println("HTTP文件目录服务器启动，网址是 : " + "http://localhost:" + port + url);
            future.channel().closeFuture().sync();

        } finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }

    public static void main(String[] args) throws Exception {
        int port = 8765;
        String url = DEFAULT_URL;
        new HttpFileServer().run(port, url);
    }
}
